Push button operating mechanism for permeability tuning purposes



March 14, 1.944. M. J. KIRK 2,344,091

PUSH BUTTON OPERATING MECHANISM FOR PERMEABILITY TUNING PURPOSES Filed Feb. 20. 1939 4 Sheets-Sheet 1 23- Q I h .52

I i 5 I i )1 5 3 INVENTOR 34 5 7 Marlin J iii/"1K ATTORNEY M. J. KIRK March 14, 1944.

. PUSH BUTTON-OPERATING MECHANISM FOR PERMEABILITY TUNING PURPQSES 4 Sheets-Sheet 2 Filed Feb. 20, 1939 INVENTOR ATTORNEY. v

March 14, 1944. J K R 2,344,091

PUSH BUTTON OPERATING MECHANISM FOR PERMEABILITY TUNING PURPOSES Filed Feb. 20, 1939 4 Sheets-Sheet I5 25 "I. I "N.

|Iil'1IiIilimiiiIllIiiimiIIiiiliiimliiiiiiiiliiiliI! u 45? E 37 4 ATTQRNEY.

2,344,091 PUSH BUTTON OPERATING MECHANISM FOR PERMEABILITY TUNING PURPOSES M. J. KIRK March 14, 1944.

Filed Feb. 20, 19:59 4 Sheets- Sheet 4 INVENIOR MarZz'mJKz'r/t BY fluj 0. ATTORNEY.

reamed M ir-i, 1944 1 I 2,344,691 rush nu'r'ron orsaama C MECHANISM son rnnmaannm rnarosss Martin J. Kirk, Chicago, 111.. minor to Johnson Laboratories, Inc., Chi

of Illinois cage. 11]., a corporation 1 Application February zo, 1e39, sesame. 257,313

'21 Claims.

Myinvention relates to operating devices for inductors having variable inductance by relative movement of the coils and ferromagnetic cores of said inductors, the inductance variationbeing thus effected by changing the, permeabil ity of the magnetic paths of the inductors, which,

where said inductors are used as parts of reso-" nant circuits, -is an effective means for tuning tends through the mounting plate, and-is-provided' with motion multiplying devices. so that limited movement of a selected push-button,

' 1 which is in the direction of theselected key-bar,

said resonant circuits over a desired range of frequencies, for example over the broadcast band.

My invention relates particularly to'mechanismof the kind referred to, in which a. plurality of- 1 push-button mechanisms capable of reciprocating movement may be selectively operated to establish different conditions, of inductance, or

. tuning to a desired frequency by said selection, as

the desired inductancesor to tune the several resonant circuits to a selected frequency, as the case-maybe.

Withoperating. mechanism of the push-button type, it is desirable that the lrey bars shall not be required, toha've excessive movement, that is to say, the finger-i of the operator should move only a limited distance for convenience and comfort in operatingthemechanismsay for example Vi'to Vs". nd Ye at the same time the inductors which are conveniently varied as to their induct ance by movement of their ferromagnetic cores,

the case may be, in combination with a plurality of. inductors having variable inductance and operated by the push-button mechanism to secure ring to the accomp is transformed from straight line motion into rotary motion; said motion is then multiplied and v the. multiplied motion'is again transformed into straight line motion to operate the cores of the,

inductors.

By my invention I also provideimproved means by which any one of the push -button devices may be adjusted as desired, to secure any amount of operation of the coresof the inductors, within the range of movement of said cores, and in this way any desired inductance values may be se- P lecte'd by said push-button devices, or any'particular frequencies may be tuned selectively by said push-button devices where the inductors are parts of resonant circuits, as the case maybe.

My invention will be, best understood by 'referg drawings illustrating a preferred embodime thereof, in which:

Fig. 1 illu'strates'my operating mechanism in irontelevation; I

' Fig. 2 illustrates my operating mechanism in rear elevation;

.Fig; '3 is a horizontal, sectional view through a part of the construction shown in Figs. 1 and 2,

are provided with operating" mechanism which generally is required to move through much greater distances, since the coils ,of-the inductors are preferably of relatively small diameter and I large length, and the cores emploved therewith are of corresponding proportions for example the cores may be from 1%" to 2%" long. This indicates the need for motion-multiplying mechanism of some kind between the push-button mechanism and the operating devices directly associated with the cores. Ag in. on account of'it being desirable to have the movement of the push-button mechanism of a' reciprocating na,- ture, for example by means of longitudinally movable key-bars, I flndit advisable to mount the reciprocable push-button mechanism on one side of a mounting plate and to mount the inductors with their longitudinally movable cores on the other side of said mounting plate, to the end that the. complete mechanism may occupy as. small bulk as possible. To accomplish this, '1 provide by my invention rotary mechanism conncct ing the push-button mechanism. with the cores of the inductors. which rotary mechanism extaken along theline '3-3 in Fig. 1;

Fig. 4 is a horizontal, sectional view through a part of the construction shown in Figs. 1 and 2.

' taken along the line 4-4 in Fig. -1;

I line l-JinFigJl;

taken along the line 5-5 in Fig. 1;

Fig. 5 is a horizontal, sectional view through'a part of the construction shown in Figs. 1 and Fig. 6 is avertical, sectional view through a part of the key-bars, taken along the line 6-4 inFig. 1;

Fig. 7 is a front elevation of the structure shown inFig. 6;

, Fig; 8 is a horizontal, sectional view or the structiire shown in Figs.,6 and line 8-8 in Fig. '7;

Fig. 9 is a vertical, sectional view ofa part of the structure shown in Fig. 2, taken along the 7, taken along the Fig. 10 shows in a view ifled form of-operating mechanism;

Fig. 11 isa vertical, sectional view of the structure shown in Fig. 10, taken along the line "-4 .in Fig. 10;

Fig. 121s a vertical, sectional view to an enlarged scale through he key-bar sbowninl'ig. 1i. taken alongthe line lI-ilinl'ig. 11;

similar-to Fig. 1 a and.

Fig. 15 is a plan view to an enlarged scale of a modified form of sector for use with the construction oi'the operating mechanism illustrated in Figs. 1 and 2; and a Fig. 16 is a side elevation of the sector construction shown in Fig. 15.

Similar numerals refer to similar parts'throughout the several views.

As shown in Fig. 1, my invention consists of a mounting plate Ill supporting upper and lower horizontal plates II and 12 which are slotted as illustrated in Figs. 3 and 5, to form guides for key-bars l3 and to maintain said key-bars in vertical position, for the position of the mecha" nism as a whole which is illustrated in Figs. 1 and 2. Each of the key-bars l3 carries Just below the plate H a sector 14 of sheet metal pivotally connected with the key-bar at It, which sector canries two lugs Na and Nb extending in opposite directions from the sector, the lugs a, as shown in Fig. 1, extending towards the observer and the lugs Mb extending away from the observer. Each oi the key-bars i3 carries a key-rod l6 extending above the corresponding key-bar and having rigidly secured to its upper end a finger button or knob I'L. The rod is supported for rotary movement by a flange member l8 formed from the key-bar l3, and at its lower end the rod is threaded, as more clearly shown in Fig. 6, to engage the horizontal leg or an angle member l9 extending through the key-bar l3 and so posi tioned that its vertical leg lies against the outer vertical surface of the sector ll, as a result of which, when the rod I6 is turned by the button 11 to slightly raise the horizontal leg .of the angle member IS, the vertical leg or said angle member presses tightly against the flat surface of the sector ll and'thereby presses the sector tightly against the key-bar to clamp the sector in any position to which it may be adjusted, without producing a binding action between the angle member I! and the-threads on the rod it. As shown in Figs. 6 and '7, the pivotal connection II of the sector M also secures to the sector and key-bar a perforated clip 20 to receive one end of a key-bar returning spring 2|, as shown in Fig. 2,

the other end of said spring engaging the top horizontal plate II. t

Each of the key-bars n is constructed as above described.

The horizontal plates II and 12 are. held in place; by side plates 22 and 23 secured 'to the mounting plate l0, and said side plates also support in vertical position a bearing'platedl extending horizontally across the front lower portion of the device to support shafts)" and as in horizontalposition, the shaft 25 extending through the mounting plate II or a purpose below described and the shaft 20 having its ends suhstan tially flush with the outer surfaces or the mount ingplatelllandthebcaringplatefl.

As illustrated in m. '1, the mains rigidly secured thereto a bell crank member 2Phaving arms 21a and 2'") extending in diametrically opposite directions from the shaft and in dinerent planes as illustrated iii-F18. 5, said bell crank member having a third crank arm 21c extending from the shaft "at substantially right angles to tively. The outer ends of the arms 21a and 280 are pivotally connected with vertical members 29a extending downwardly from atransverse bar 28 disposed adjacent the key-bars l3 below the sectors ll, so that the upper edge of said transverse bar 29 is below and in line with the lugs No on the sectors H, as illustrated in Fig. 4. The bell crank arms 21b and 2811 are pivotally connected with a second transverse bar 30 of the same construction as the bar 29, which bar 30 is 15 disposed adjacent the opposite sides of the key-bars l3 and below the sectors It, so that its upper edge is below and in line with the lugs lab on the sectors H. The arms 21c and 280 of the bell crank members 21 and 28 are pivotally connected by a third transverse bar 3|.

The arms of the bell crank levers 21 and 28 are all of the same efiective length, and thev shafts 25 and 28 are spaced a substantial distance apart, as a result of which the bars 29, 3B and 3i are 25 maintained in parallel relation with each other at all times, and any rotary movement imparted to either of the shafts 25 and 26 is effectively communicated to the other shalt to rotate it substantially the same amount. It will further be observed that on account of the relation of the arms 21a and 21b to each other, and the similar rela-- tionship oi the arms 28a and 28b, any movement imparted to one of the bars or 30 by rotary movement of either of the shafts 25 and 26 will be accompanied by similar and opposite movement of the other of said bars, that is to say, it Ior any reason the bar 2! is moved downwardly, the bar 30 is at the same time moved upwardly, and it at the beginning of operation of either of the-shafts 25 and 25 the bar 30 happens to be uppermost and the bar 30 is then moved downwardly, the bar 281s moved upwardly.

The bars 28 and are so disposed relatively to the sectors that when any one of the keybars is depressed, one oi the lugs Ila and llb on thesector of the selected key-bar will engage A one, of the transverse bars 29 and 30, depending on which of said bars is uppermost, and that continued downward movement of the selected key-bar will de ress the uppermost transverse bar 20 or" an move it downwardly until the other enact the lugs a or iron the selected sector ll engages the other of the transverse bars 28, andllI, whichlimits further downward movement of the selected key-bar. Thus in any case one of the transverse bars 29 and operates as an operating bar-and the other of said bars operates as a stop bar when any one oi the key-bars is operated, It will be observed that '60 the angular position of the sector l4 on any one of the key-bars I3, determines the maximum amountot transverse movement'that may be imparted to thebars 2! and 30 by the lugs Ila and llb on said sector, that is to say, when said lu'gs are in nearly horizontal alignment the amount 0! transverse movement imparted to said bars 28 arid. 30 is relatively small, and when said sector is adjusted angularly so that one of the lugs Ma and [lb is in its'uppermost position,

the amount of possible movement imparted to the bars 2! and ll by said lugsis a maximum In this way,--by adjustment or any sector l4 on 1 its key-bar II, the amount '0! rotary movement imparted to the shafts 2i and 18 by depression the arms 21a and 21b and in substantially the 5 oi the corresponding key-bar, may be adjusted as desired; It .will also be observed that gardless of the position of the transverse bars 2a and 30 at'the beginning of their operation by a selected one of the sectors l4, when the selected key-bar is depre a definite relation to each other vertically'ythat sse'd until it will so no. further, the transverse bars 29 and will occupy is to say, any particular adjustment oia selected one of the sectors l4 on its key-bar will have the effect for operation of the' corresponding keybar, of always mowing the transverse bars in said connections, and springs 53 and 53' reand 30 to the seine position, and therefore moving the shafts 'and 26 to the same angular position, as long as the angular position ofthe sector on the selected key-bar is maintained. It will also be observed that by releasing the sector on any key-bar by turning the key-rod It, the corresponding sector maybe moved angularly on its key-bar to eiiect any desired position vertically of the transverse bars 28 and 30 and any desired angular position of the shafts 25 and 28, within the range of the mechanism.

As shown in Figs. 2'and 4, insulating tubes 32 r are supported in horizontal position substantially parallel with the mounting plate It by an end flange Ilia formed on the mounting. plate and by a plate/33 of insulating material supported in verticalposition by said mountin plate. The tubes 32 carry inductance coils l4 and contain with a sliding fit ferromagnetic cores 35, the ends of which cores have secured to them slender rods 38 threaded at their outer ends to engage thin-walled insulating sleeves 31 held firmly' in engagement with a vertically extending yoke 138 by resilient clips 39 which,

as more clearly shown in Fig. 9, are secured to the yoke 38 by any suitable means, for example rivets 40.

As shown in Fig. 2, the mid-portion of the yoke 38 is rigidly secured to one end of a horizontal bar 4| supported in sliding engagement with a flange member 42 formed from the mounting plate Ill. The shaft 25, where it projects through the back face of the mounting plate It, has rigidly secured thereto a crank 43 pivotally connected at 44 with the mid-portion of a lever 45, the lower end of which is pivotally connected at 46 with the mid-portion of the yoke as. The

upper end of the'lever." is" pivotally connected at 41 with one end 10f a link 40, the other end of which is pivotally connected at 49 with the mounting plate ill. The distance from the axis of the shaft 25 to the center of the pivotal connection 44 is equal to the center-to-center distanc'e of the pivotal connections 44 and 46, and

'spectively carried bylthe yoke II and the lever 45, engage the pivotal connections 46 and 44 to eliminate lost motion from those connections.

The insulating sleeves 31 are in threaded engagement with the slender rods 38 and the pressure of the resilient clips 39 is suillcient to hold said threaded rods against turning in said sleeves unless itis desired to adjust the cores II relatively to the coils or relatively to each other, which may readily be done by turning the threaded rods in the sleeves for aligning or tracking purposes.

\ Asshown in Fig. 4 the upper portions of the key-bars i3 and the sectors l4 carried thereby are located in inclined and overlapping positions as to saidsectors, to reduce to a minimum the total width of the housing required to contain a given number of key-bars, and to at the same time displace the lugs Ma and Nb carried by each sector' in a direction from front to rear of the device, a suflicient amount to so space 'the transverse ,bars 29 and 30 from front to rear of'rthe device that the lower portions of the keybars may pass freely between them and still be disposed vertically below the said lugs respectively. The key bars ll just-below sectors l4 are twisted slightly so that their lower portions are in substantially the same plane and substan-- tially parallel with the mounting p ate Ill,v as shownin Fig. 5. As illustrated in Fig. 5, the

to manually a just the cores 35.

In using the device described, to tune resonant circuits of which the coils 34 may be parts, for

example in radio receivers constructed to cover a given range of frequencies, such as the broadis also equal to the center-toe-c'enter distance-of the pivotal connections 44 and 41, and the length of the link 48 and the position of its pivotal support 49 are so chosen as to place the pivotal connection, 41 vertically over the axis of the shaft 25 and to place the link 48 in horizontal position,

assuming that, as shown in Fig. 2, the cores l5 and the yoke 38 are to be moved horizontally.

length oi the link 48. To limit the slight error introduced by the use of thelihk' 48, angular movement of the crank 43 and shaft II is limited to substantially 90 by stop lugs and II formed from themounting plate ll, said possible movement being substantially equally divided on either side of avertical line the axis of the cast band, the sectors l4 may be conveniently adjusted so that the corresponding key-bars will v severally tune the resonant circuits to diiferent frequencies and corresponding stations of said band in the following manner: Any desired station of said band may -be carefully tuned by means of the finger knob 54,-and then with the cores 35 in the position given them to effect said tuning, thev rod 16 of the desired key-bar is turned to release the angular clamp l9, and the selected key-bar I3 is depressed until the transverse bars 28 and 30 ensage the lugs (rand Nb of the selected sector l4,which operation turns the sector on its pivotal support l5, and further downward movement of the selectedkey-bar is prevented bysaid transverse bars. The rod l6 is then'turned to Press the angularclamp l9 against the sector l4 and in that way to clamp thesector-tightly against the key-bar, which holds the sector in its adjusted position and at the same time tightens the rod it. against accidental turning. Thereafter, and unless the sector l4 is again-adjusted, operation of the selected keybar will always move the cores 1! to the required position to tune the resonant circuits containing the coils ,toth'e frequency of the desired station, regardless of the position of the transverse bars 28 and 30 at the beginning of the downward movement 01 the selected key-bar, and

downward movement of the selected key-bar will be in every case limited and stopped by said transverse bars 29 and 30, when the cores #5 In Figs. -14, inclusive, I illustrate a modified form of my operating mechanism which differs from that above described, in that each of the key-bars when actuated to mov the ferro-mag-' netic cores to a particular position relatively to the coils associated with said cores, is retained in its depressed position by suitable locking mech anism below described, against the action of a spring tending to move said cores to one of their extreme positions, which is their position of rest until and unless they are moved therefrom by one of the key-bars and held in said moved position by the locking mechanism referred to. With the construction 'illustrated in Figs. 1-9 inclusive, each key-bar is moved to its uppermost position by its returning spring 2i when the downward actuating pressure on said key-bar is released and the cores 2! remain in the position to which they have been movedby the operation of said keybar without any tendency to move from that position.

As shown in Fig. 10, the device consists of a mounting plate Iiib supporting horizontal plates I Ia and Ho to hold key bars I3ain vertical position for sliding movement through said horizontal plates.- Each of the key-bars supports a rod lid for turning movement in a flange member Ila formed from said key-bar, a stop washer "Ilb being carried by said rod below the flange memto restrain the rod Ita from accidental turning movement. The transverse bars 29, 80 and 3 I the shafts 25 and 28, the cranks 21 and 28 and the manner of supporting the transverse bars from the shatts by said cranks, are the same as illustrated in Fig. 1 and above described, the keybars Ila extending vertically between the transverse bars 28 and 30, said shafts and 28 being supported by the mounting plate I01) and a bearing plate 24a. In the construction shown in Figs. .10 and 11, the sole purpose of the bars 30 and iii is to maintain corresponding angular rotation of the cranks 21 and 28.

As shown in Figs. 11 and 14, the shaft 25 has rigidly secured thereto a finger knob 54 for manually operating the cores 35, said cores, the coils 84 and their manner of support, and the operating mechanism provided to operate said cores by turning movement 01 the shaft 25, being the same as above described in connection with Fig. 2, the only difference being that in Fig. 11 I illus trate the adaptation of my improved mechanism to operate three cores respectively associated with three inductance coils 34, as illustrated in Fig. 11, instead of using but two 01 said coils and associated cores as illustrated in Fig. 2. It will be understood that with either form of operating mechanism, any desired number of inductors may be used within the practical limits of the device. With the construction 01 Figs. 10-14,; inclusive, the shaft 25 carries a returning spring 58 which engages the bearing plate 24a and the knob 54, and serves to hold the cores 35 in their innermost position in the coils 34 her Ila to prevent longitudinal movement or the I rod Ita through said flange member. The lower -end of the rod I6a' is threaded and extends 7 through threaded openings in a U-shaped member 35 supported for vertical sliding movement on and relatively to the key-bar Ila. The-member I is secured ment relatively to the key-bar with the member I. the connection being eflected by arivet 51 or the equivalent, extending through a longitudinal slot II in the key-bar Ila. a more clearly shown in Flgs.,l2 and "13. As shown in Figs. 12 and 13,

the member "has formed iromfthe lower end thereof a tongue Blaextending into the slot II to *prevent turning movement 01' the member N on the key-barrlia, and said member is also pro;-

vided with a lug lib to engage the transverse bar 20 illustrated in Fig. 10, when the key-bar Ha is depressed. The U-shaped member II illustrated in Figs. 10 and 12 is preferably so made that its normal position}; as indicated, in dotted lines in' P18. 12 from which position it is sprung to the position indicated in full lines and threaded in that position to lit the threads on the rod Ita.

. To insert thi-threads on the rod Ila into the threaded openings in the member I, said inemberis spnmg to its position shownirriull lines, and alter the threadedportion oi. the rod has been extehded openings in the member II, the pressure on the member is released and the spring tension oi the member; exerts sumcientpressure'on the threads toan operating member 58' mounted on theopposite side or the key-bar Ila for moveunless they are moved to some other position by the operating mechanism illustrated in Fig. 10, and held in their operated position.

As shown in Fig. 11, each of the key-bars I3a is providedat its lower end portion with a recess Ilb to receive the lower edge of a swinging latch bar 60 pivotally supported at the ends of its opposite edge at BI by bearing members 62 supported by the side walls carried by the mounting plate MD. A spring 63 is provided to press the lower edge of the latch bar 60 against the edges of the key-bars Ila and to hold said latch bar in the recesses I3b. when all of said key-bars are in"their uppermost position, to which they are moved by returning springs 64 unless held in operated position by said latch bar. Each of the key-bars Iia is provided with an edge notch I3c above the recess I3!) and spaced from said recess by an amount representing the stroke of the key-bar a. As a result of this construction, when a selected one of the key-bars Ila is depressed, ithe lower edge of the latch bar 60 is moved away from its locking'positioh, which serves to release any key-bar on key-bars that may have previously been actuated, the lug 56b engages and operates-the transverse bar 29 and thereby similarlyoperates the cores 3!,which operation continues until the notch I30 is in line with the lower edge of the latch bar SI) for which'position of the key-bar the. latch bar enters the notch Iic under the action 0! the spring 82, and holds the key-bar in its depressed position, thus holding the cores 3! in their operated position, against the action of the returning spring 59. The amount oi operation thereby imparted to the cores 35 is determined by the 1 position of the operating member 56 on the keythrough both of the threaded I of movement possible with the throw of the keybar "a, the construction above described permitting said operating member 56 to have any desired position on said key-bar, within the range j claim is: v

bars permitted by notches c.

The construction illustrated inl igs. 10-14, in-

, clusive, has the advantage of taking up lost motion in the various operating connections involved and it has the further advantage of indicating the selection that has been effected by the operation of the key-bars. On the other hand, the eonstruction illustrated in Figs. 1-9, inclusive, has

the advantage of positively moving the cores I! in either direction, instead of relying on a spring to move them in one direction, as is the case with v arsena the 'locatio'n of the locking Ibar extending across the paths of movement of different amounts to tune a resonant radio cirthe construction illustrated in' Figs. 10-14, inclusive. A further advantage of the construction illustrated in-Figs. 1-9, inclusive, is thatless operating pressure is require onthe push buttons than with the other construction, inasmuch as it is not necessary to overcomethe pressure of a core returnin spring, inaddition to the friction of the parts and the pressures of the key-bar returning springs. I l

In Figs. and 16 I illustrate a construction of sector'llc which may beemployed with the op erating mechanism illustrated in-Flgs. 1-9, in-

Q clusive, in which the sector consists of sheet metal cult to a desired one of a range 'of frequencies, the combin'ationof a mounting plate for support- -ing the inductance device on one side of said plate 1 na first plane parallel with said plate 5 and with the core movable substantially parallel with said plate, a plurality of selective operating key-devices mounted on the other-side of said i plate in a first plane parallel with said plate 'for rectilinear movement substantially parallel 2o therewith, and transfer mechanismincluding a shaft extending through. said plate and adapted for operating connection with said core, said transfer mechanism having operative relation with said operating key-devices imparting to 5 said shaft different amounts of angular movehaving integral lugs [4d and He formed by suitabletools from parts of the sheet metal from which the body portion of the sector is formed,

By my invention I have therefore provided effective means for transforming thelreciprocating movement of a selective push-button mechanism into rotary movement, and then again transcores of variable inductance devices, and-at the same-time multiplying the movement imparted to said cores, most of the parts of which'mech'a nism may be cheaply produced by stamping operations, since the. parts for any one of said selec-- tive devices are duplicates of parts of the rest of said selective devices.

While I have shown my invention in the par-.

ticular embodiment above described, it will be understood that I do not limit myself thereto as I may employ equivalents thereof without departing from the scope of the appended claims,

Having thus described my invention what I ment determined respectively by said operating key-devices, each'of said operating key-devices including a first and longitudinally reciprocable bar, and a member 'carriedby said first bar and movable thereon to different positions of adjustformed said rotary movement into reciprocating movement to operate the longitudinally movable .ment effecting different amounts, of' angular movement of said shaft for a given amountof movement of said first bar, said transfer mecha nism including a second bar connected with I 5 said shaft and mounted thereon for transverse angular and parallel movement to operate said shaft said second bar extending across the paths and in the range of movement of the adjustable A members on the bars of said key-devices for operation by said key-devices an amount dete'r- 1. In a selective operating mechanism for a variable inductance device of the class wherein the inductance device includes a coil and a ferromagnetic core movable longitudinally relatively, to said coil to selectively adJ'ust the inductance of the device to any desired'one of a plurality of. different amounts to tune aresonant' i radio circuit to a desired one of a rangeof frequencies, the combination of a 'mounting plate for supporting the inductance device on one side of said plate in a-first pianeparallelywith said plate and with the core movable substantially parallel with said plate, a plurality of selective 1 operating key-devices mounted on the other side of said plate in a second plane parallel with said plate for rectilinear movement substantially parallel therewith, and transfer mechanism including a shaft extending through said plate and adapted for operating connection withzsaid core, said transfer mechanism having operative relation with said operating key-devices imparting to said shaft different amounts 'of angular movement determined respectively by said operating key-devices, said transfer mechanism ineluding a bar connected with said shaft and mounted thereon 'for transverse angular and parallel movement to operate said shaft, said mined in any case by the adjustment of the opcrating adjustable member.

3. In a selective operating mechanism for a variable inductance device of the class wherein the inductance device includes a coil and a ferromag'netic core movable longitudinally-relatively to said coil to selectively adjust the inductance ofthe device to any desired one of a pluralityof different amounts to tune a resonant radio circuit to a desired one of a range of frequencies, the combination of a mountingplate for sup-- portingthe inductance deviceon one side of said plate in a first plane parallel with said plate and with the core movable substantially parallel with said plate, a plurality of selective operating key-devices mounted on the other side of said plate in a second plane parallel with saidplate for rectilinear movement substantially parallel therewith, and transfer mechanism including a shaft extending. through said plate and adapted for operating connection with said core, said transfer mechanism having operative relation with said operating key-devices imparting to said shaft different amounts of angular movement determined respectively by said operating key-devices, each of said operating key-devices including a first and longitudinally reciprocable bar, and a member carried by, said first bar and movable thereon to different positions of adjustment effecting different amounts of angular I movement of said shaft for a given amount of .movement of said first bar, said transfer mechanism including second and third bars each connected with said shaft and mounted thereon for transverse angular and parallel movement to opand the other of said second and third bars becomes a stop bar stopping further movement of the operating adjustable member by en ement therewith.

4. In a selective operating mechanism for a variable inductance device of the class wherein the lnductancedevice includes a coil and a ferromagnetic core movable longitudinally relatively to said coil to selectively adjust the inductance of the device to any .desired one of a plurality of diflerent amounts to tune a resonant radio circuit to a desired one of a range of frequencies, the combination of a mounting plate for supporting the inductance device on one side of said plate in a first plane parallel with said plate and with the core movable substantially parallel with said plate, a plurality of selective operating keydevices mounted on the other side of said plate in a second plane parallel with said plate for I rectilinear movement substantially parallel therewith, and transfer mechanism including a shaft "extending through said plate and adapted for operating connection with said core, said transfer mechanism having operative relation with said operating key-devices imparting to said shaft different amounts of angular movement determined respectively by said operating key-devices, each of said operating key-devices including a first and longitudinally reciprocable bar, a sector pivotally carried by each of said first bars and movable angularly thereon to different positions of adjustment effecting different amounts of angular movement of said shaft for a given amount of movement of said first bar, and clamping means for holding said sector in adjusted position on said bar carrying said sector, said transfer mechanism including a second bar connected with said shaft and, mounted thereon for transverse angular and parallel movement to operate said shaft,; said second bar extending across the paths and in the range of movement of the sectors on the bars of said key-devices for operation by said key-devices an amount determined in any case by the adjustment of the operating sector, each'of said sectors including a lug projecting perpendicularly therefrom for engaging and operating said second bar.

5. In a selective operating mechanism for a variable inductance device of the class wherein the inductance device includes a coil and a ferromagnetic core movable longitudinally relatively to said coil to selectively adjust the inductance of the device to any. desired one of a plurality of diflerentamounts to tune a resonant radio circuit to a desired one of a range of frequencies, the combination of a mounting plate for supporting the inductance device on one side of said plate in a first plane parallel with said plate and with the core movable substantially parallel with said plate, a'plurality of selective operating key devices mounted'on the other side of said plate in a second plane parallel with said plate for with, and transfer mechanism including 1' shaft extending through said plate and adapted for operating connection with said core, said transfer mechanism having operative relation with said operatingkey-devices imparting to said shaft different amounts of angular movement determined respectively by said operating key-devices, each of said operating key-devices including a first and longitudinally reciprocabie bar, a sector pivotally carried by each of said first bars and movable angularly thereon to different positions of adjustment effecting different amounts of angular movement of said shaft for a given amount of movement of said first bar, and clamping means for holding said sector in adjusted position on said bar carrying said sector, said transfer mechanism including second and third bars each connected with said shaft and mounted thereon for transverse angular and parallel movement to operate said shaft, each of said second and third bars extending across the paths and in the range of movement of the sectors on the bars of saidkey-devices for operation by said key-devices of an amount determined in any case by the adjustment of the operating sector, said second and third bars being mounted and connected for movement in opposite directions,

whereby the one of said second and third bars first engaged in any case by an operating sector depending upon the initial position of said shaft, becomesthe operated bar, and the other of said second and third bars becomes a stop bar stopping further movement of the operating sector by engagement therewith, each of said sectors including two lugs oppositely' disposed and projecting oppositely and perpendicularly from the sector for operating and stop engagement with said second and third bars,

6. In a selective operating mechanism for a variable inductance device including two elements one of which is movable relatively to the other, the combination of two parallel shafts,-

angularly aligned cranks of the same eil'ective radius secured to said shafts, a bar articulating with and connecting'said cranks, the center-tocenter distance of said bar connections being equal to the center-to-center distance between said shafts, selective key bars in alignment with and directed transversely of said bar for moving said bar different amounts laterally, and operating connections between one of said shafts and the movable element of said inductance device.

7. .In a selective operating device for variable inductance mechanism including a coil and a ferromagnetic core movable longitudinally relatively to said coil for radio tuning purposes, the combination of a plurality of selective operating key-devices mounted for rectilinear and substantially parallel movement, and transfer mechanism including a rotary shaft for operating conriection with the movable element of said inductance mechanism, said transfer mechanism having operative relation with said operating key-devices imparting to said shaft different. amounts of angular movement determined re-- spectively by said operating key-devices, said rectilinear movement substantially parallel theretransfer mechanism including a bar connected with said shaft and mounted thereon for transverse angular and parallel movement to operate said shaft, said bar extending across the paths oi' movement of and adjacent to said key-devices for operation by any selected one of said keydevices.

8.1a a selective operating device for variable inductance mechanism including a coil and a therewith.

, 3,344,091 ferromagnetic core movable longitudinally reladifferent positions'of adjustment effecting different amounts of angular movement of said shaft for a given amount of movement of said first bar, said transfer mechanism including a second bar connected with said shaft and-mount-' ed thereon for transverse angular and parallel movement to operate said shaft, said second bar adjustment eifecting different amounts of angu-, lar movement of said shaft for a given amount of movement of said first. bar, said transfer mechanism including second and third bars each contial position of said shaft, becomes the operated nected with said shaft and mounted thereon for transverse angular and parallel movement tooperate said shaft, each of said second and third bars extending across the paths and in the range of movement of the adjustable members onthe bars of said key-devices for operation by-said key-devices an amount determined in any case' by the adjustment of the operating adjustable member, said second and third bars being mounted and connected for movement in opposite directions, whereby the one of said second and v third bars first engaged in any case by an operating adjustable member depending upon the inibar, and the other of said second and third bars becomes a stop bar stopping further movement extending across the patljs and in the range of movement of the adjustable members on the bars of said key-devices for operation by said keydevices an amount determined in any case by the adjustment of the operating adjustable member.

of the operating adjustable member by engagement therewith.

11. In a selective operating device for variable inductance mechanism including a coil and a ferromagnetic core movable lcngitudinally rela- 9. In a selective operating device for variable inductance mechanism including a coil and a ferromagnetic core movable longitudinally relativelyto said coil for radio tuning purposes, the

combination of a plurality of selective operating key devices mounted for rectilinear and substantially parallel movement, andgtransi'er mechanism inclliding a rotary shaft for operating connection withv the movable element of said inducting operative relation with said operating keydevices imparting to said shaft different amounts of angular movement determined respectively by- I said operating key-devices, said transfer mechanism including first and second bars each can-- neoted with said "shaft' and mounted thereon for transverse angular and parallel movement to operate said shaft, eachof said first and second main including a rotary shaft for operating connection with the movable element of said induct- 4 tively to said coil for radio tuning purposes, the combination of a plurality of selective operating key-devices mounted for rectilinear and substantially parallelmovement, and transfer mechaance mechanism, said transfer mechanism having operative-relation with said operating key-" ldevices imparting to said shaft different amounts of angular movement determined respectively by ance' mechanism, said transfer mechanism havsaid'operating key-deviceaeach of said operating key-devices including a first and longitudinally reciprocable .bar, a sector pivotally carried byeach of said first bars and movable angularly 40 thereon to' different positions of adjustment efsaid sector in adjusted position on said bar carfecting different amounts of angular movement of saidshaft for a given amount of :movement of said first bar, and clamping means for holding 43 rying said sector, said transfer mechanism inbars extending across the paths of movement of being mounted and connected for movement in opposite directions, whereby the one of said first and second bars first engaged in any case by any selected one of said key-devices depending upon the'initial position of said shaft, becomes the operated bar, and the other or said first and secdo ond bars \becomes a-stop bar stopping further movement of the selected key-bar by engagement said key-devices for operation by anyselected one bf .said Hey-devices, said first and-second bars eluding a second'bar connected with said shaft and mounted thereon for transverse angular and parallel movement to operate said shaft, said second bar extending across the paths and in the range of movement of the sectors on the bars of said key-devices for operation by said key-de- 10. In a selective operating device for variable ferromagnetic cdre movablelonglmdmany re1a inductance mechanism including a coil and a ferromagnetic core movable longitudinally relatively to said coil for radio tuningv purposes, the combination of a plurality of selective operating key devices mounted for rectilinear and substantially parallel movement, and transfer mechanism including a rotary'shaft for operating connection .with the movable element of said inductance mechanism, said transfer mechanism having opoperating key-devices, each of said operating key-- devices including a first andlongitudinally reciprocable bar, and a member, carried'by said first vices an amount determined in any case by the adjustment of the operating sector, each of said sectors including a ing projecting perpendicularly therefrom for engaging and operating said secl and bar. v

l2.v In a selective'operating device for variable inductance mechanismv including a coil and a tively to said coil for radio tuning purposes, the combination of a plurality of selective operating key-devices mounted for rectilinear and substantially parallel movement,

ing connection with the movable element of said inductance'-mechanism, said transfer mechanism having operative relation with said oper- 'ating key-devices imparting torsaid shaft dif-,

7 ferent amounts of angular movement determined respectively by said operating key-devices, each of said operating key-devices including a first and longitudinally reciprocable bar,a sector pivotally carried by each of said first bars and movbar and movable thereon to different positions 013 able angularly thereon to different positions of a v and transfer' 05 mechanism including a rotary shaft for ope'rat- 'the bars of said key-devices for operation by said key-devices of an amount determined in any case by the adjustment of the operating sector, said second and third bars being mounted and connected for movement in opposite directions, whereby the one of said second and third bars first engaged in any case by an operating sector depending upon the initial position of said shaft, becomes the operated bar, and the other of said second and third bars becomes a stop bar stopping further movement of the operating-sector by engagement therewith, each of said sectors including two lugs oppositely disposed and projecting oppositely and perpendicularlyfrom the sector for operating and stop engagement with said second and third bars.

13. In a selective operating mechanism for a variable inductance device including two elements one of which is movable relatively to the other, the combination of two parallel shafts, a first pair of angularly aligned cranks secured respectively to said shafts,'a second pair of angularly aligned cranks secured respectively to said shafts and displaced angularly from the cranks of said first pair, the cranks of each pair having the same effective radius, a first bar articulating with and connecting the first pair of cranks, a second bar articulating with and connecting the second pair of cranks, the center-to-center distance of the crank connections of each of said bars being equal to the center-to-center distance between said shafts, selective key-bars in alignment with and directed transversely of said first and second bars for moving said first and second bars laterally and thereby imparting different amounts of angular movement to each of said shafts, and operating connections between one of said shafts and the movable element of said inductance device, said first and second barsbeing mounted for simultaneous movement in opposite directions, whereby said first and second bars are interchangeably an operated bar and a stop bar for said key-bars depending upon the positions of said first and second bars at the beginning of the operation of any selected one of said key-bars.

14, A radio tuner including in combination, frame means including a front portion and a back portion, a plurality of control units, with each of said control units including linearly movable control means on said frame means and available for operation at the, front portion thereof, additional control means supported on said frame means at the back portion thereof and movable in a linear direction, and motiontransferring means intermediate said two linearly moving means and operatively associating the same including means for converting linear movement into rotary movement in the motiontransferring means and then converting the rotary movement into linear movement in the. additionallinearlv movable control means, saidcontrol units including selectively operable key bars having respectively operating sectors pivotally mounted thereon and determining the amounts of operating movement of said key bars.

15. A radio tuner including in combination. frame means including a front portion and a back portion, a plurality of control units, with each of said control units including linearly movable control means on said frame means and available for operation at the front portion thereof, additional control means supported on said frame means at the back portion thereof and movable in a linear direction, and motiontransferring means intermediate said'two linearly moving means and operatively associating the same including means for converting linear movement into rotary movement in the motiontransferring means and then converting the rotary movement into linear movement in the additional linearlymovable control means, said control units including selectively operable key bars each carrying means changing as desired its amount of operating movement.

16. A radio tuner including in combination, frame means including a front portion and a back portion, a plurality of control units, with each of said control units including linearly movable control means on said frame means and available for operation at the front portion thereof, additional controlmeans supported on said frame means at the back portion thereof ing the same including means for converting linear movement into rotary movement in the motion-transferring means and then convertin the rotary movement into linear movement in the additional linearly movable control means, said control units including selectively operable key bars each having a member movable thereon changing as desired its amount of operating movement.

17. A radio tuner including in combination, frame means including a front portion and a back portion} a plurality of control units, with each of said control units including linearly movable control means on said frame means and available for operation at the front portion thereof, additional control means supported on said frame means at, the back portion thereof and movable in a linear direction, and motiontransferring means intermediate said two linearly moving means and operatively associating the same including means for converting linear movement into rotary movement in the motiontransi'erring means and then converting the rotary movement into linear movement in the additional linearly movable control means, said motion-transferring means including a laterally movable bar for operating actuation in common by said control units.

' 18. A radio tuner including in combination,

frame means including a frontportion and a back portion. a plurality of control units, with each of said control units including linearly movadditional linearly movable control means, said motion-transferring means including a first and laterally movable bar for operating actuation in common by said control units and includin also a second bar laterally movable by and oppositely to said first b'ar ior'in common stopping movement of said control units.

19. A radio tuner including in combination. frame means including a front portion and a back portion, a plurality of control units, with each of said control units including linearly movable control means on said frame means and available for operation at the front portion thereoi, additional control means supported on said frame means at the back portion thereof and movable in a linear direction, and motion-transi'erring means intermediate said two linearly moving means and operatively associating the same including means for converting linear movement into rotary movement in the motion transferring means and then converting the rotary movement into linear movement in the additional linearly movable control means, said control units including selectively operable key bars each carrying means changing as desired its amount. of operating movement, said motiontransferring means including a bar extending acrom the paths of movement of said key bars for lateral operating movement by a selected one of said key bars.

20. A radio tuner including in combination. frame means including a front portion and a back portion, a plurality of control units, with each of said control units including linearly movable control means on said frame means and available for operation at the front portion thereof, additional control means supported on said frame means at the back portion'thereoi and movable in a linear direction. and motiontransierrlng means intermediate said two linearly moving means and operatively associating the same including means for converting linear movement into rotary movement in the motiontransferring means and then converting the rotary movement intolinear movement in the additional linearly movable control means, said control units including selectively operable key bars each having a member movable thereon changing as desired its amount of operating movement, said motion-transferring means in-' cluding a first bar extending across the paths of movement, of said key bars for lateral operating movement by a selected one of said key bars, and including also a second bar extending across the paths of movement of said key bars and laterally movable by and oppositely to said first bar for stopping movement of a, selected key bar.

21. A radio tuner including in combination, frame means including a front portion and a back portion, a plurality of control units, with each of said control units including linearly movable first control means on said frame means and available for operation at the front portion thereof, additional control means-supported on said frame means at the back portion thereof and movable in a linear direction, motiontransferring means intermediate said two linearly moving means and operatively associating 1 the same including means for converting linear movement into rotary movement in the motiontransferring means and then converting the rotary movement into linear movement in the additional linearly movable control means, and devices returning said first control means to its original condition after each operation and leaving said additional control means in its operated condition.

MARTIN J. KIRK.

CERTIFICATE or ponfiitq'hojv Patentlio. 2,31 l;,091.- 11mm 11;, 19M.

mumx J. 1mm.-

It is hereby certified that error appears in'the.brinted eneeiflcltion of the above numbered patent requiring correction a followe Pnge 1, first column, line 56, for 'unploved" reici -eu1 ileyed-; line 37, after proportioms' insert I. come; page 5, second 061mm, line 11;, claim 2, for plate 1 m reed -p1nte 1n 1; line 18, nme claim, for 'flret'renqeoond";

"and thlf the said Letters Patent should be read with this eorreo tign therein that the sane may confom to the record of the one in the Petent 01'- ricer Signed and eenled m1; 36m a or m A. n. 1f9 l;b,

Leslie Fraz'er (Seal) Actingco miniaaioner of Patents.

I CERTIFICATE OF'QOWHOjv Patentllo. 2,5hh,o91.- Hirch 11;, 19111;.

, MARTIN J. 1cm;

It is hereby certified that error nppeu l in'the.iarinted egeoifleation or the above numbered petent requiring corree'tion a tollowe Page 1, flrat column, line 56, for 'emploved' rei'ci --eupiley ed---; 1111037, after "proportiona" insert a comma; page 5, second c olmmi ine 1h, claim-2, for "plate 5. m rend plate in a"; line 18, same claim, for "flret' renq --eecon d--; ma that the tall-1d Letters Patent should be reed with m; eorreetign therein thu't the seme may confom to the record of the chic in the Patent Ot Signed. end sealed m1; lth day or 11 1 n. 91m

Leslie Fra'z'er (Seal) Actin0oinin1as1oner 0 1 Patents. 

